Type I collagen is one of the major skin proteins and it is a triple helix protein composed of two strands of α(alpha)1 (I) chain and one strand of α(alpha) 2 (I) chain. Type I collagen is produced by fibroblasts in the skin dermis and it forms an extracellular matrix in which the fibroblasts are embedded. Both intrinsic aging and photoaging are accompanied with reduced collagen production and increased activity of collagenase (Non-Patent Documents 1 to 3). Thus, it has been believed that a promotion of collagen production leads to suppression and/or improvement of a skin condition caused by intrinsic aging or photoaging, for example, wrinkle formation. In fact, it is known that retinoids, i.e., derivatives of vitamin A, have an efficacy when applied to the face or upper arm skin caused by intrinsic aging or photoaging (Non-Patent Documents 4 and 5). However, the retinoids have a side effect like photosensitization or inflammatory reaction known as a retinoid reaction (Non-Patent Document 6). Further, having generally high photoreactivity, the retinoids need to be protected from light for stable storage. Thus, after administration to the skin, the retinoids may be easily decomposed by light penetrating a living body under ordinary living conditions.